There is no way to know if you'll keep your gains or not. It depends on how far past your genetic limit the steroids took you. Most people these days do not wait until they are near their genetic limit to start using steroids. They want a short cut. So if you go straight to steroids you're likely to lose your gains because it was the steriods keeping you at that size.
The other problem with going straight to steroids is that you never build mature muscle mass to build on. You're creating all new muscle mass and that's much harder to keep. It is the people who get their mass built up and then use steroids to go further that keep most of their gains. The other thing is unreal expectations. Ronnie Coleman averaged 8 pounds of lean mass a year. It's ridiculous for people to think they can add twice or three times that on the doses that are commonly used on this board.
The other problem with going straight to steroids is that you never build mature muscle mass to build on. You're creating all new muscle mass and that's much harder to keep. It is the people who get their mass built up and then use steroids to go further that keep most of their gains. The other thing is unreal expectations. Ronnie Coleman averaged 8 pounds of lean mass a year. It's ridiculous for people to think they can add twice or three times that on the doses that are commonly used on this board.